1. Field of the Invention
The present invention relates to paint-applying rollers to which paint is supplied under pressure, and in particular to a seal for such a roller.
2. Description of the Prior Art and Related Application
Various types of paint-applying rollers are known in the art wherein the paint is supplied under pressure to an interior of the knap-carrying roller, and is forced through interior apertures of the roller so as to saturate the knap permitting a user to continuously apply paint to a surface. Such power fed rollers are described, for example, in U.S. Pat. Nos. RE29311; 2,955,310; 3,145,411; 3,193,368; 3,549,267; 3,554,659; 3,809,484; 3,826,581; and 4,217,062.
All of the above rollers exhibit the problem of leakage of the paint or other fluid supplied under pressure to the interior of the knap-carrying tube which is used to apply the paint to a surface. The knap-carrying tube must necessarily rotate with respect to a stationary interior part to which the paint or other fluid is supplied under pressure. A means permitting flow of the paint or other liquid through the knap-carrying tube must also be present, that is, the knap-carrying tube and the stationary element to which the paint is suplied must be in fluid communication. In order to permit application of paint or other liquid along the entire length of the knap of the roller, the tube or roller is rotatably supported at the ends thereof in the above devices. A problem in this technology resides in the design of a means permitting rotation of the roller with respect to the interior paint supply means which does not permit leakage of paint or other liquid out of the ends of the roller.
A paint roller assembly is disclosed in the co-pending application of Rudolf R. Karliner and Gerald E. Peterson, Ser. No. 602,206 filed on Apr. 19, 1984, and assigned to the assignee of the present application, Wagner Spray Tech Corporation. That assembly includes a hollow roller arm, a delivery tube within the roller arm which receives pressurized liquid, such as paint, the tube terminating in a horizontally disposed end portion. The end portion is received in a roller core and also functions as a shaft about which a perforated knap-carrying tube rotates. The roller core has an opposite end face having another shaft extending therefrom. The knap-carrying tube has end caps each having an interiorly extending tube for respectively receiving the shafts of the roller core. Engagement of the shafts within the end cap tubes permits rotation of the knap-carrying tube with respect to the roller core.